Seems the IP address for the http://sr.planet.wikimedia.org cannot be found. Not quite sure the DNS record for the sr.planet has been enabled or not.
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>ping sr.planet.wikimedia.org
Ping request could not find host sr.planet.wikimedia.org. Please check the name
and try again.
>tracert sr.planet.wikimedia.org
Unable to resolve target system name sr.planet.wikimedia.org.